Fast radio burst

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A fast radio burst (FRB) is a transient celestial radio pulse lasting only a few milliseconds, and thought to be of extra-galactic origin, though this notion is contested.[1]

Lorimer burst[edit]

D. R. Lorimer and others analyzed archival survey data and found a 30-jansky dispersed burst, less than 5 milliseconds in duration, located 3° from the Small Magellanic Cloud, which became known as the Lorimer burst.[2] They reported that the burst properties argue against a physical association with our Galaxy or the Small Magellanic Cloud. In a recent paper, they argue that current models for the free electron content in the universe imply that the burst is less than 1 gigaparsec distant. The fact that no further bursts were seen in 90 hours of additional observations implies that it was a singular event such as a supernova or merger of relativistic objects.[3] It is suggested that hundreds of similar events could occur every day and, if detected, could serve as cosmological probes. Radio pulsar surveys such as Astropulse-SETI@home offer one of the few opportunities to monitor the radio sky for impulsive burst-like events with millisecond durations.[4]

Further developments[edit]

In 2010 there was a new report of 16 similar pulses from the Parkes radio telescope which were clearly of terrestrial origin,[5] but in 2013 four pulse sources were identified that supported the likelihood of a genuine extragalactic pulsing population.[6]

An observation in 2012 of an FRB (FRB 121102) in the direction of Auriga in the northern hemisphere using the Arecibo radio telescope has confirmed the extragalactic origin of fast radio pulses by an effect known as plasma dispersion. Victoria Kaspi of the Max Planck Institute for Radio Astronomy also confirms the initial estimate of 10,000 FRB's per day over the entire sky.[7]

Theories[edit]

Because of the isolated nature of the observed phenomenon, the nature of the source remains speculative. As of 2013, there is no generally accepted explanation. The emission region is estimated to be no larger than a few hundred kilometers. If the bursts come from cosmological distances, their sources must be very bright.[8] One possible explanation would be a collision between very dense objects like black holes or neutron stars. Blitzars are another proposed explanation.[8] It has been suggested that there is a connection to gamma ray bursts.[9]

References[edit]

  1. ^ "Fast Radio Bursts Might Come From Nearby Stars", Harvard-Smithsonian centre for Astrophysics
  2. ^ Chiao, May (2013). "No flash in the pan". Nature Physics 9 (8): 454–454. doi:10.1038/nphys2724.  edit
  3. ^ D. R. Lorimer, M. Bailes, M. A. McLaughlin, D. J. Narkevic, F. Crawford (2007-09-27). "A Bright Millisecond Radio Burst of Extragalactic Origin". Science. Retrieved 2010-06-23. 
  4. ^ Duncan Lorimer (West Virginia University, USA), Matthew Bailes (Swinburne University), Maura McLaughlin (West Virginia University, USA), David Narkevic (West Virginia University, USA) and Fronefield Crawford (Franklin & Marshall College, USA) (October 2007). "A bright millisecond radio burst of extragalactic origin". Australia Telescope National Facility. Retrieved 2010-06-23. 
  5. ^ Sarah Burke-Spolaor; Matthew Bailes; Ronald Ekers; Jean-Pierre Macquart; Fronefield Crawford III (2010). "Radio Bursts with Extragalactic Spectral Characteristics Show Terrestrial Origins". arXiv:1009.5392v1 [astro-ph.CO].
  6. ^ D. Thornton, B. Stappers, M. Bailes, B. Barsdell, S. Bates, N. D. R. Bhat, M. Burgay, S. Burke-Spolaor, D. J. Champion, P. Coster, N. D'Amico, A. Jameson, S. Johnston, M. Keith, M. Kramer, L. Levin, S. Milia, C. Ng, A. Possenti, W. van Straten (2013-07-05). "A Population of Fast Radio Bursts at Cosmological Distances". Science. Retrieved 2013-07-05. 
  7. ^ "Radio-burst discovery deepens astrophysics mystery"
  8. ^ a b "A Brilliant Flash, Then Nothing: New “Fast Radio Bursts” Mystify Astronomers", Scientific American
  9. ^ V. Ravi, P. D. Lasky (2014-05-20). "The birth of black holes: neutron star collapse times, gamma-ray bursts and fast radio bursts". Monthly Notices of the Royal Astronomical Society. Retrieved 2014-08-29.